Recent radiotelephones have incorporated low profile designs. Low profile designs typically include a thin light-weight cover member which "flips" over the radiotelephone body when the radiotelephone is closed and "flips" above and away from the radiotelephone body when the radiotelephone is opened. As such, this member is called a "flip." The radiotelephone also includes an antenna element which during operation extends above the radiotelephone body. Radiotelephones have conventionally used various types of translating antennas such as side-mounted swivel antennas and telescoping antennas. In any event, the antenna and flip typically stow adjacent to the radiotelephone body when closed and extend above the radiotelephone body when opened.
In a preferred low-profile application, the antenna is configured as a flexible "blade" or "strip" (i.e., a flexible strip transmission line) radiating element which can be very narrow, thin, and flexible. The blade antenna can rotate and extend similar to the flip described above. However, this flexibility can result in unwanted deformation and unappealing gaps in the cover when the flip and antenna are in the closed or stow position. Further, during use, the blade antenna can be subjected to use or abuse which can misalign or deform the blade or strip antenna. As such, over time, it can be very difficult for the flip and strip antenna to maintain a desirable aesthetic cover shape that can repeatedly rotate between the open and closed positions.
In addition, in operation, the blade antenna and the flip typically rotate above and away from the radiotelephone body such that a user can position the flip adjacent his or her ear. Unfortunately, extension of the strip antenna adjacent the flip can subject the radiotelephone to reduced sensitivity due to blocked signals or interference caused by the position of the antenna relative to the user's anatomy (typically the head). Further, antennas typically have preferred operative positions which is controlled by a user. Unfortunately, the user can improperly extend the antenna or position the antenna such that it is subject to unwanted interference.
Objects and Summary of the Invention It is therefore an object of the invention to provide a radiotelephone with a low-profile flip and strip or blade antenna configuration which is structurally tolerant of repeated openings and closings.
It is an additional aspect of the invention to provide a radiotelephone with an improved flip and flexible strip antenna mounting structure which can reduce the interference associated with the user during operation.
It is another object of the present invention to provide a radiotelephone with a mounting structure which provides an RF signal path for a strip antenna which can improve sensitivity and reduce interference associated with the position of the antenna in use over that of conventional antennas used with flip radiotelephones.
It is still another object of the present invention to provide a mounting structure and associated method which can facilitate the antenna's translation into preferred operative positions.
These and other objects of the present invention are satisfied by the present invention, which is directed to a radiotelephone having a biasing structure associated with a flat blade antenna which biases the antenna to open toward a preferred operative position. A first aspect of this invention is an antenna and flip hinge assembly for a radiotelephone, wherein the assembly comprises a radiotelephone body with first and second end portions and a flat blade antenna pivotably attached to the radiotelephone body first end portion. The radiotelephone also includes a flip member pivotably attached to the radiotelephone body first end portion. The flip member is attached on the first end portion spaced-apart from the flat blade antenna. The flat blade antenna and the flip member are individually rotatable from a first stow position, in which each of the flat blade antenna and the flip member are positioned to overlie the radiotelephone body, to a second open position, in which the flip member and the flat blade antenna are positioned above and extend longitudinally away from the radiotelephone body relative to the stow position. The flip member moves through a first angle of rotation relative to the radiotelephone body and the flat blade antenna moves through a second or additional angle of rotation relative to the radiotelephone body, with the second angle of rotation being greater than the first angle of rotation. The assembly includes a biasing structure which is operably associated with the blade antenna. The biasing structure is configured to bias or pre-dispose the antenna to rotate toward the open position, preferably beyond the first angle of rotation (i.e., past the flip member). In a preferred embodiment, the biasing structure is configured to provide a variable rotational force or torque vector which increases and then decreases during both deployment and closure of the flat blade antenna to bias the antenna to the open and stow positions.
A second aspect of the invention is an antenna hinge assembly for a radiotelephone. The antenna hinge assembly comprises a radiotelephone body having a hinging portion with a first cavity. A cylindrical bearing retainer comprising an outer surface and an inner cavity is positioned in and affixed to the radiotelephone body first cavity such that the bearing retainer transversely extends a distance out of the radiotelephone first cavity. The antenna hinge assembly also includes a blade antenna having a lower portion with a transversely extending shell with an inner wall. The shell is sized and configured to receive a portion of the bearing retainer therein. The blade antenna is pivotably attached to the radiotelephone body hinging portion such that the shell inner wall rides on the bearing retainer outer surface as the blade antenna rotates during use. The blade antenna is rotatable from a first stow position, in which the blade antenna substantially overlies the radiotelephone body, to a second open position, in which the blade antenna longitudinally extends above and away from the radiotelephone body. The assembly also includes a detent cam having a cam surface operably associated with the blade antenna positioned intermediate the blade antenna and the body hinging portion and a detent spring operably associated with the detent cam. The blade antenna rotates from the first stow position to the second open position. Preferably, a variable (increasing and then decreasing) turning force is introduced onto the blade antenna to facilitate the advancement of the blade antenna toward a preferred operational or open position. In a preferred embodiment, the detent cam, the detent spring, and the blade antenna pivotable attachment, define a biasing structure which biases the blade antenna toward the open position. It is also preferred that the detent cam surface be configured to introduce variable turning forces on the blade antenna to bias the blade antenna forward and facilitate the return of the blade antenna back to the stow position during closing.
An additional aspect of the present invention is similar to the antenna assembly above, but incorporates a flip member mounting structure as well. This embodiment is directed to a flip and antenna hinge assembly for a radiotelephone which comprises a radiotelephone body with a hinging portion with transversely extending first and second cavities. Each of the cavities have opposing first and second ends and are spaced-apart. The assembly includes first and second cylindrical bearing retainers. The first bearing retainer comprises an outer surface and an inner cavity positioned in the first cavity of the radiotelephone body hinging portion such that the first bearing retainer transversely extends a distance out of one end of the first cavity. The second bearing retainer comprises an outer surface and an inner cavity positioned in the second cavity of the radiotelephone body hinging portion such that the second bearing retainer transversely extends a distance outside one end of the second cavity. The assembly also includes a blade antenna having a lower hinging portion pivotably attached to the radiotelephone body hinging portion. The blade antenna lower hinging portion is sized and configured to receive a portion of the first bearing retainer therein. The blade antenna is rotatable from a first stow position, in which the blade antenna substantially overlies the radiotelephone body, to a second open position, in which the blade antenna longitudinally extends above and away from the radiotelephone body. The assembly further includes a flip member having a lower hinging portion pivotably attached to the radiotelephone body-hinging portion. The flip member is configured to receive a portion of the second bearing retainer therein. The flip member is rotatable from a first stow position, in which the flip member substantially overlies the radiotelephone body, to a second open position, in which the flip member longitudinally extends above and away from the radiotelephone body. The assembly additionally includes a detent cam with a cam surface is operably associated with the blade antenna and is positioned intermediate the blade antenna and the radiotelephone body hinging portion and a detent spring operably associated with the detent cam. Preferably, as the blade antenna rotates from the first stow position to the second open position, the blade antenna is biased or predisposed to turn or advance beyond or to a preferred position (preferably beyond the flip open position).
In a preferred embodiment, the detent cam surface introduces variable rotational turning forces on the blade antenna to facilitate the return of the blade antenna to predetermined angular positions during closing. Also, it is preferred that the blade antenna opens beyond about 180 degrees to travel to the open position (and beyond the flip member) relative to the stow position.
Another aspect of the present invention is a method of mounting a flat blade antenna and flip member to a radiotelephone. The method comprises the steps of pivotably mounting a flat blade antenna to an end portion of the radiotelephone and separately pivotably mounting a flip member to the same end portion of the radiotelephone. A biasing structure is also mounted to the radiotelephone end portion so that the blade antenna is biased to travel beyond a predetermined position angle of rotation in the opening direction such that the blade antenna travels through a greater angle of rotation than the flip member to bias the blade antenna away from the flip member in the open position. Preferably, the biasing structure mounting step includes assembling the biasing structure so that it introduces a variable rotational turning force vector onto the blade antenna during opening. In a preferred embodiment, the variable rotational force vector increases at about 180 degrees from the stow position and decreases thereafter to facilitate the blade antenna opening to above 180 degrees from its stow position.
The present invention is advantageous because the low turning force dual hinge mounting structure allows the flip and antenna to be individually rotated in a manner which can protect the flexible blade antenna from deformation, handling abuse and wear, and provides an appealing aesthetic appearance. In addition, the rotation of the blade antenna separate from the flip allows the antenna to be positioned during use such that it minimizes interference with the anatomy of the user. The low-force mounting structure allows the antenna to be easily positioned in preferred positions during use. In addition, in a preferred embodiment, the design of the mounting structure biases or pre-disposes the antenna to open and close into preferred operative and stow positions. The forward biasing structure also facilitates the antenna to translate and open beyond the flip during use thereby reducing interference with a user by spatially separating the flip and the antenna and positioning the antenna away from the user.